Teaching Case

Laryngeal trauma evaluated on CT imaging

A 26 year old male was involved in a motor vehicle accident striking his neck on the steering wheel. On physical examination there were neck pain and tenderness, hoarness and stridor. Indirect laryngoscopy demonstrated edema and ecchymosis of both arytenoid and also the reduced mobility of the left true vocal fold. CT was performed and revealed a dislocated fracture of the left thyroid lamina of the thyroid cartilage, that produced mild airway narrowing. These injuries were considered reversible without surgical intervention. At 30 days after injury both the voice and airway were good, but indirect laryngoscopy showed the persistance of a reduced mobility of the left true vocal fold.

Laryngeal trauma can be divided in three groups according to Schaefer classification: the first group comprises laryngeal hematoma or edema; the second group comprises the presence of laryngeal hematoma associated with laryngeal mucosa injuries, subcutaneous emphysema or fractures of the cartilagineous skeleton; massive hematoma, paralysis of the vocal folds and penetrating injuries represent the third group. The keystone for successful treatment of acute laryngeal trauma and hence for prevention of serious consequences are an early and accurate evaluation of the site of injury using indirect laryngoscopy and CT imaging. CT is strongly advocated as the most important diagnostic tool for laryngeal trauma; it permits a rapid, non-invasive examination of the laryngeal skeleton that previously was obtained only with direct laryngoscopy or open exploration. CT visualizes well the laryngeal skeleton, soft tissue and arirway in the injuried larynx; even if MR imaging is more accurate for depicting the laryngeal soft tissues damages and permits coronal and sagittal scans. CT findings actually can directly influence the form of management. Literature reports suggest spontaneous resolution of laryngeal injuries when the injury is limited to a nondislocated fractures; in this case according to CT findings of a minimally dislocated fracture of thyroid lamina of the thyroid cartilage, surgical exploration was omitted because spontaneous resolution was felt to be likely.